HOVHANNISYAN v. ARMENIA JUDGMENT 11 [GC], no. 54810/00, § 68, ECHR 2006-IX), or if it shows a lack of respect for, or diminishes, human dignity (see Svinarenko and Slyadnev v. Russia [GC], nos. 32541/08 and 43441/08, §§ 118 and 138, 17 July 2014). 50. The Court further reiterates that where an individual raises an arguable claim that he or she has been seriously ill-treated by the police or other agents of the State in breach of Article 3, that provision requires by implication that there should be an effective official investigation. The obligation to carry out an effective investigation into allegations of treatment infringing Article 3 suffered at the hands of State agents is well established in the Court’s case-law (see Bouyid, cited above, §§ 114-123), and for the most recent authority, Jeronovičs v. Latvia [GC], no. 44898/10, § 103, ECHR 2016). 51. In order to be “effective”, such an investigation, as with one under Article 2, must firstly be adequate (see Ramsahai and Others v. the Netherlands [GC], no. 52391/99, § 324, ECHR 2007-II, and Mustafa Tunç and Fecire Tunç v. Turkey [GC], no. 24014/05, § 172, 14 April 2015). This means that it must be capable of leading to the establishment of the facts and to a determination of whether the force used was or was not justified in the circumstances and of identifying and – if appropriate – punishing those responsible (see, inter alia, Giuliani and Gaggio v. Italy [GC], no. 23458/02, § 301, ECHR 2011 (extracts); Mustafa Tunç and Fecire Tunç, cited above, § 172; Jeronovičs, cited above, § 107; and Armani Da Silva v. the United Kingdom [GC], no. 5878/08, § 233, ECHR 2016). An obligation to investigate “is not an obligation of result, but of means”: not every investigation necessarily has to be successful or come to a conclusion which coincides with the claimant’s account of events (see D.M.D., cited above, § 40). 52. The investigation of serious allegations of ill-treatment must also be thorough. That means that the authorities must always make a serious attempt to find out what happened and should not rely on hasty or illfounded conclusions to close their investigation or as the basis of their decisions. They must take all reasonable steps available to them to secure the evidence concerning the incident, including eyewitness testimony, forensic evidence, and so on. Any deficiency in the investigation which undermines its ability to establish the cause of injuries or the identity of the persons responsible will risk falling foul of this standard (see Mikheyev v. Russia, no. 77617/01, § 108, 26 January 2006, and Virabyan v. Armenia, no. 40094/05, § 162, 2 October 2012). 53. Allegations of ill-treatment contrary to Article 3 must be supported by appropriate evidence. To assess this evidence, the Court adopts the standard of proof “beyond reasonable doubt” but adds that such proof may follow from the coexistence of sufficiently strong, clear and concordant inferences or of similar unrebutted presumptions of fact (see, among other authorities, Ireland v. the United Kingdom, cited above, § 161 in fine;